VSync Off - How is target FPS achieved?

Hello,

Would you have some information of how TD achieves a target FPS such as 60FPS without Vsync On ?

In OF (ofAppRunner | openFrameworks) they sleep in-between frames :

“show_ofSetFrameRate - Attempts to set the frame rate to a given target by sleeping a certain amount per frame.”

Is the same method used in TD ?

Thanks